448 SALMON AND TROUT. 
or the wood-work only may be ‘charred.’ Varnish or paint, 
however, preserves the zinc, and prevents oxidation. ‘The 
punctured pipe must be raised a quarter of an inch from the 
bottom, by means of little feet soldered on, as in case any fish 
escape from the trays in manipulation, they would be killed by 
attempting to get under the pipe if it is laidon the bottom. It 
is often necessary to ¢izn out the young fish, and the bottom of 
the troughs thus gives a large amount of extra space, and the 
fish can be drawn off by the waste pipe when required. 
One looks back with much interest to the time when these 
experimental operations were commenced. How well I re- 
member my first day’s trout spawning ; how careful I was that 
the can containing the freshly taken ova should not be shaken 
on the journey of three miles home: the least jostling or 
swinging of the can sent a feeling of horror through me ; and 
what 2n excited state of uncertainty I was in for the first few 
weeks, wondering whether with all the clumsiness in taking 
the eggs, any of them would ‘hatch out.’ I have since 
learned that freshly taken ova can be sent long distances by 
rail without danger, and I prefer to send them in water rather 
than moss, as they can be transferred to the hatching troughs 
more quickly, and with less risk of concussion. The ova will 
not bear the same amount of shaking and disturbance forty- 
eight hours afterwards, but they may be examined with a glass 
tube, and carefully replaced in the troughs without injury, 
from the day of taking: anything approaching concussion, 
however, kills them, until the tissues of the fish are firm and 
their eyes are visible. 
THE COLLECTION OF OVA. 
When everything in the hatching-house has been tested, and 
ascertained to be thoroughly sound and in order, the ova is to 
be procured. ‘First catch your hare,’ is applicable here. T 
remember in former years the great uncertainty and risk there 
